METAR is the scheduled observation taken at the end of each hour. SPECI is an observation taken at an unscheduled time due to certain criteria that are met such as low visibility, low clouds, frozen precipitation, or thunderstorms.

KORD-Station ID

In this example, K refers to a US Station and ORD is the three letter id for O' Hare (from Orchard Field, its original name). Other examples are KRFD (Rockford Il), KAMA (Amarillo, TX) and KDEN (Denver, Co).

041656Z-Time and Date

The 04 represents the day of the month.

The 1656 represents the time at which the observation went out.

The Z represents that the time is in ZULU or UTC (Coordinated Universal Time).

19020G26KT-Winds

The 190 (the first three numbers) is the direction of the winds in degrees from 0 to 360 degrees (although you will never see 360 because after 359, it goes back to 0).

The 20 (next two numbers) is the speed of the winds in knots.

the G26 represents the wind gusts. In this case the gusts are 26 knots. Gust will not always be on here...there are criteria which must be met in order to have a gust. Simply, unless it's windy, you are not going to see gusts in the obsevation.

the KT simply means knots. It will always be at the end.

For winds speeds below 7 knots, you might see VRB005KT which means the wind direction is variable. This is the idea of "light and variable" that you might see in a forecast.

For winds greater than 6 knots you might see 18015KT 150V210. The winds are from 180 degrees at 15 knots, but the direction is actually variable between 150 degrees and 210 degrees. In order to be variable above 6 knots, the winds must have at least a 60 degree variation.

6SM-Visibility

The 6SM simply means 6 Statute Miles. Occasionally you might see visibility up to 20 or 30 SM but for the most part it will go from < 1/4 (vis below 1/4 SM) up to 10 SM.

(-SHRA)-Present Weather and Obscurations

(-) is the designator for light. Precipitation will either be light (-), moderate ( ), or heavy (+) based on certain criteria that must be met. For more info on those criteria, please see the FMH-1 link at the bottom of this page. For now, just understand that it is simply the intensity of the snow, rain, hail, sleet, or freezing rain.

SH means showers and RA means rain. So the present weather is a light rain shower.

The following is from the FMH-1 HANDBOOK. The entire handbook is linked at the bottom of this page.

QUALIFIER

WEATHER PHENOMENA

INTENSITY OR PROXIMITY 1

DESCRIPTOR 2

PRECIPITATION 3

OBSCURATION 4

OTHER 5

- Light Moderate (see note 2)

+ Heavy

VC In the Vicinity (see note 3)

MI Shallow

PR Partial

BC Patches

DR Low Drifting

BL Blowing

SH Shower(s)

TS Thunderstorm

FZ Freezing

DZ Drizzle

RA Rain

SN Snow

SG Snow Grains

IC Ice Crystals

PL Ice Pellets

GR Hail

GS Small Hail and/or Snow Pellets

UP Unknown Precipitation

BR Mist

FG Fog

FU Smoke

VA Volcanic Ash

DU Widespread Dust

SA Sand

HZ Haze

PY Spray

PO Well-Developed Dust/Sand Whirls

SQ Squalls

FC Funnel Cloud Tornado Waterspout (see note 3)

SS Sandstorm

SS Duststorm

The weather groups shall be constructed by considering columns 1 to 5 in the table above in sequence, i.e. intensity, followed by description, followed by weather phenomena, e.g. heavy rain shower(s) is coded as +SHRA

To denote moderate intensity no entry or symbol is used.

Tornados and waterspouts shall be coded as +FC.

BKN070-Sky Condition

BKN represents a broken sky. (The clouds cover 5/8 to 7/8 of the sky)

110 represents the clouds are at 11,000 feet (simply add 2 zeroes to get the height)

You will often have more than 1 designator (i.e. SCT035 BKN090 OVC140)

An indefinite ceiling caused by fog, rain, snow, etc., will require a designator as VV (Vertical Visibility). VV is the how high you can see vertically into the indefinite ceiling.

Significant Clouds such as TCU (Towering Cumulus), CB, (Cumulonimbus, or a shower/thunderstorm), or ACC (Altocumulus Castellanus) will be found on the end of a category (i.e. SCT035TCU)

12/08-Temperature and Dewpoint

12represents the temperature in Celcius

08represents the dewpoint in Celcius

If the temperature or dewpoint falls below 0 there will be an "M" before it (i.e. 03/M02). "M" means minus.

30.16-Altimeter/Pressure

A simply stands for Altimeter

3016 means 30.16 inches of mercury for the pressure.

RMK AO2-REMARKS

RMK simply means REMARKS and marks the end of the standard metar observation and the beginning of the remarks that are put in as necessary.

A02 means that the site is automated and HAS a precipitation sensor. If it were AO1, there would be no precip sensor. This does not mean the site is un-manned. If there is an AUTO after the ID in the metar ob, then there is no observer.

There are many remarks, and the FMH-1 (Federal Meteorological Handbook-1) at the bottom will give you a full listing of them. Here are only a few of the important and common remarks: